System and method for retrieving information from an information carrier by means of a capacitive touch screen

ABSTRACT

The present invention relates to a method comprising providing one or more information carrier(s) with a dielectric and/or conductive pattern and a detection device having a capacitive touch screen and inducing an interaction between the information carrier and the touch screen, wherein the interaction is based on a difference in the dielectric coefficient and/or the conductivity of the pattern and generates a touch signal and wherein the interaction is induced by relative motion between the information carrier and the touch screen. The invention further relates to a system comprising an information carrier comprising a dielectric and/or conductive pattern which encodes information and a detection device having a touch screen; the detection device is able to decode the information upon interaction between the information carrier and the touch screen, wherein the interaction is caused by a difference in the dielectric coefficient and/or the conductivity of the pattern.

TECHNICAL FIELD

The present invention generally refers to a method and system comprisingan information carrier and a detection device having a touch screen, anda method to read out the information on the information carrier with thedetection device.

BACKGROUND OF THE INVENTION

During the past decades, there has been a rapid development in dataprocessing and storing. In the field of information technology, amultitude of media to store information has been developed. They includefloppy disks, compact disks (abbreviated as CD's), digital versatiledisks (known as DVD's), USB flash drives, multitude of data cards andnumerous other devices. However, these devices storing information haveseveral properties limiting their field of application.

Compared to classical data storage (such as printed information) theyare much more complex and therefore harder to produce. This makes themless economic in certain applications. It is for example hard to imaginethat these devices could replace bar codes placed on articles in adepartment store. Though all these devices can easily perform the taskof storing the (very limited) amount of data for the article (e.g. nameof article, price, serial number, date of expiry, etc.), they are toocomplex and thus expensive to be used in such an environment. However,there may be other applications where a data-storage device encoding thedata in an optical pattern (e.g. the said barcode) is not desirable.Though it is simple and therefore cheap to produce, it has thedisadvantage that only a very limited amount of data may be encoded withit.

Moreover, it is generally easy to counterfeit a bar code, which makes itmuch less safe than more sophisticated data storage devices. One reasonfor this is the fact that the information is encoded in a visiblepattern. Thus, copying the barcode may be enough to generate acounterfeit.

Another disadvantage of the optical pattern lies in the fact thatdeviations of the surface where the optical pattern is applied to (e.g.scratches and the like) may lead to malfunctions.

The relatively new technology disclosed in WO 2010/043422 and WO2010/051802 overcomes the disadvantages of the established prior artmentioned above. The basic idea of the information carriers presented inthese two publications is to use information carriers comprising apattern of conductive and non-conductive regions.

In comparison to storing the information in an optical pattern, thistechnology has the advantage of being a lot harder to copy (andcounterfeit). Moreover, the pattern of conductive and non-conductiveregions might not lie on the surface of the information carrier. Thus,these information carriers are much more resistant to externalinfluences, including, but not limited to, physical stress, scratches,humidity and the like.

At the same time, they can be produced in simple processes—thus makingthem much cheaper and more economic as the more complex devicesmentioned above. The fact that they are less complex further enablesthem to be used in a multitude of applications. However, for certainapplications a potential disadvantage of the information carriersdescribed in WO 2010/043422 and WO 2010/051802 may be seen in thatspecific devices are needed to read out and decode the informationstored on these information carriers (this is in fact a disadvantage ofall data storage devices mentioned above). These devices are thusspecially designed and optimized for the corresponding informationcarrier(s), which adds costs to the decoding method and system and makesit more expensive for the user.

During the rise of information technology, there has also been a rapiddevelopment in the sector of personal computers, laptops, smart phones,tablet computers and the like. In these devices, the usage of touchscreens has become more common over the last years. Touch screensusually allow the user to induce an input by touching a designated areaof these devices.

There are different technologies for these touch screens to operate,including resistive, capacitive, acoustic wave and infraredtechnologies. All these technologies are optimized to detect a humanfinger or a specially designed stylus that is brought into contact withthe touch screen.

According to recent developments, systems including touch screens canalso be used to recognize certain shapes of inanimate objects. Forexample, US 2010/0045627 discloses placing a specifically shaped object(a so-called signet) onto a touch screen, wherein the system will thencompare the shape of this signet with shapes stored in a database. Incase there is a match between the presented shape and a shape in thedatabase, it will perform an action. Examples for these actions includegiving access to restricted areas of a computer system, logging onto acertain user profile of a computer system and the like. However, thetechnology disclosed in US 2010/0045627 has several major drawbacks.First, this technology is limited to signets that are recognized by apre-stored database. Thus, the system only works and performs certainactions if it recognizes a known object. Thus, this technology islimited in its usability, in particular with regard to interpretingshapes that are new to the system. Thus, these systems cannot be used toread out and decode encoded information being new to the system. Thismeans in particular that the technology disclosed in US 2010/0045627does not allow the touch screen to be an input device for informationcarriers new to the system.

Second, the technology disclosed in US 2010/0045627 entirely relies onthe shape of the objects. The touch screen proposed in US 2010/0045627for shape recognition is particularly optimized for an input signalbeing pressure imposed by a human finger or a stylus. However, the shapeof an object is generally visible to the naked eye and furthermoredetectable by touch.

There are numerous applications where these properties aredisadvantageous. Likewise, it is desirable to establish a technology inwhich the touch screen can be used as an input device for structuresprior not known by the system.

SUMMARY OF THE INVENTION

In light of the prior art and the disadvantages of the state of the art,the technical problem underlying the present invention is to provide asystem and method which overcome the mentioned disadvantages.

This problem is solved by the features of the independent claims.Preferred embodiments of the present invention are provided by thedependent claims.

The invention relates to a method with the following steps:

-   -   a. providing one or more information carrier(s) with a        dielectric and/or conductive pattern and a detection device        having a capacitive touch screen and    -   b. inducing an interaction between the information carrier and        the touch screen, wherein the interaction is based on a        difference in the dielectric coefficient and/or the conductivity        of the pattern and generates a touch signal and    -   c. wherein the interaction is induced by relative motion between        the information carrier and the touch screen.

Useful for the present invention is particularly an information carriercomprising a dielectric and/or conductive pattern In the context of thepresent disclosure, an information carrier is preferably any object. Theinformation carrier carries encoded information, which can be simple,signed and/or encrypted. A simple information carrier may induce eventsin a device that is connected to and/or in a program (that is,preferably locally in a device). A signed information carrier mayfurther induce events in an external system to manipulate data, which isconnected via a data network. An encrypted information carrier may bedecrypted locally by a program and/or by an external data processingsystem and may then induce events in the program flow of the deviceand/or in the external data processing system.

Examples of objects include, but are not limited to printed products orobjects that can be printed on, especially playing cards, businesscards, credit cards, debit cards, stamps, signatures, postcards,(entrance) tickets and generally admission cards to restricted areas(both physical areas and virtual zones), member cards, tickets valid fora limited time, certificates (e.g., proving the origin of an object),bill of delivery and/or sale, abstracts of accounts, instructionleaflets, vouchers (e.g. for objects in computer games and/or downloadsof music, videos, e-books) and the like, but also any common productssuch as cups, glasses, consumer packaged goods, consumables andpre-products. The substrate of the information carrier may consist ofthese objects or may be attached to these objects in any suitablemanner.

The information carrier for use with the present invention providesseveral advantages over the prior art. For example, an informationcarrier comprising and/or encoding multiple information types may beprovided in a simple and cost efficient manner. Multiple information maybe used to provide for redundancy, different ranges of readability andreader-adapted functionalities (such as optic, capacitive and the like).In other words, one and the same information carrier may compriseinformation which can be read optically, resistively, acoustically orcapacitively or different bits of the information may have a differentoperating distance and may thus be read with different reading devicesor detection devices. In the sense of the invention, it is preferred,that the information carrier is read by the detection device. However,it is also possible or may be preferred to read the information carrierwith a separate reading device.

The substrate of the information carrier may be rigid or flexible.Preferably, the substrate comprises one or more of the followingmaterials: plastics, synthetic materials, paper, carton, (derived)timber products, composite materials, ceramics, glass, cloths, textiles,leather or any combination of the mentioned materials. Preferredsynthetic materials comprise PVC, PETG, PV, PETX, PE and syntheticpaper.

In the context of the present disclosure, region (which may also bereferred to as domains, structures, areas, portions, parts, divisionsand/or zones) refers to any shape, which may be one-dimensional (i.e.points or lines), two-dimensional (i.e. areas of a particular shape)and/or three-dimensional (i.e. areas with a particular height), whereingenerally two-dimensional shapes are preferred. Examples may include(but are not limited to) squares, circles, triangles, rectangles, dots,pixels and lines. Preferably, the following properties of these regionsmay be used to encode information: shape, orientation, number, distancebetween regions and/or relative position between regions.

The information can preferably comprise a coupling area. The couplingarea preferably is an area of generally conductive material on theinformation carrier itself or coupled to the information carrier andelectrically linked via conductive path(s) to one or more of theconductive regions such that the linked region(s) have the same electricpotential as the coupling area. The coupling area is preferably easilyaccessible by a user in order to set the coupling area's potential ontothe user's potential. The coupling area need not be a closed area butmay comprise a grid of conductive lines or an array of electricallyconnected structures. The coupling area is preferably electrically notexposed, i.e., covered or coated by a non-conductive material, andprovides electrical contact to the exterior of the information carrier.The coupling area may comprise the same material as the conductiveregions or a different material.

The coupling area can for example be used in such a way that the userplaces his/her finger on or close to this coupling area. Thus, theregion(s) linked to this coupling area will have substantially the sameelectric potential as the user's finger. This may be advantageous, sincetouch screens are commonly designed to work with a typical capacity of auser. The coupling area need not necessarily be directly contacted bythe user's finger, since the finger being in close proximity to thecoupling area may sufficiently influence the capacity of the couplingarea to achieve the desired effect. Preferably, the coupling area is ofthe same conductive material as the region(s) of conductive materialand/or the conductive path(s). This may allow a simple and inexpensiveproduction process.

It is preferred that the pattern encoding information imitates theproperties of fingers with respect to a signal generated on a touchscreen. In other words, the one or more regions brought into contact orat least close proximity with a touch screen generate a signal analogousto the one generated by one or more fingers touching a touch screen. Inthis context, the size, shape and/or capacitive properties arepreferably chosen to be similar to those of finger tips. It was verysurprising, that single or multi touch events can be generated by theinformation carrier.

By using the dielectric properties of the information carrier, theinformation stored or encrypted on the information carrier is no longerdirectly connected to the spatial shape. This has several advantages.The pattern does typically not affect the surface of the carrier whichallows for a much more versatile use of the information carrier comparedto the signets known from US 2010/0045627.

Advantageously, the coupling area comprises conductive lines, e.g. agrid, which preferably extend over substantially one side of thesubstrate. Thus, a user need not to touch the information carrier at aspecific location, but may touch the grid at any location in order toelectrically connect himself to the conductive regions. Alternatively,the user may bring his finger or fingers into close proximity of thecoupling area to sufficiently affect the coupling area's capacity.

It is also preferred that the coupling area extends to at least one edgeand/or corner of the information carrier. If the carrier is placed ontoa touch screen it is most convenient to touch the carrier at its edgeand/or corner. Thus, the coupling area extending to at least one edgeand/or corner of the information carrier may ease the access thereto. Anextension to an edge or corner does also encompass the situation,wherein only a small gap between the edge or corner and the couplingarea is provided, the gap, e.g., being smaller than 5 mm, preferablysmaller than 3 mm.

As the read out of the information stored on the information carrier isto be performed by a touch screen, it is preferred that the surface ofsaid pattern is substantially flat. In the context of the presentapplication, substantially flat corresponds to a generally 2-dimensionalarea with deviations at the transition between the substrate and theregion of generally less than 200 μm, preferably less than 50 μm, morepreferably less than 5 μm perpendicular to the surface. This, ingeneral, depends on the method of application: While in the case ofscreen printing the applied print layer typically has a thickness ofabout 5 to 50 μm, layer thicknesses of less than 2 μm may be achieved bycold foil transfer methods. In the case of inkjet printing (e.g. a metalcontaining ink) the pattern may be as flat as the substrate (due to itsnatural roughness). However, it may also be preferred that the patternencoding the information is not formed as a top layer (i.e. the layer onthe surface). It may also be preferred that the pattern is formed in allthree spatial directions, e.g. by applying different layers withdifferent two-dimensional “sub patterns” on top of each other. Also, thepattern may be covered by another non-conductive layer. There may alsobe one or more conductive layers behind the layer encoding theinformation as long as there is no electric contact between theadditional conductive layers and the layer encoding the information.

Examples where the present invention can be used include (but are notlimited to) access to restricted areas (both physical and virtual),usage of restricted data, usage of restricted hardware, franking,prepayment, postal charges, logistic of goods, applications in marketingand/or sale, customer loyalty, assurance against adulteration, copyrights, pay-back programs, device control, lotteries, applications forpayment and the like.

Preferred materials for a second or third material are: metals such asaluminum, lead, iron, gold, copper, magnesium, tungsten, zinc, tin,graphite, chrome, molybdenum; carbon black; dielectric materials;materials containing metals such as foils or films with a metal (e.g.aluminum) layer.

Preferably, the second and/or third material is applied onto thesubstrate by additive and/or subtractive methods, preferably by printingor laminating the second and/or third material onto the substrate. Inadditive methods, the second and/or third material is readily appliedonto the substrate. This may happen in one or more steps of production.Additive methods include, but are not limited to, printing, laminating,transfer and coating methods, for example the methods described in WO2010/043422. In subtractive methods, the second and/or third material isadded onto the substrate in excess. In one or more following steps,parts of the second and/or third material are removed (e.g. by laserprocedures and/or cauterization). For both methods, printing the secondand/or third material onto the substrate is an easy and economicprocedure to achieve the desired pattern and thus preferred. Yet, othermethods are also encompassed by the present invention. Preferably, theinformation carrier comprises layers of substrate and/or the secondand/or third material.

Furthermore, it may also be advantageous to provide an informationcarrier with two or more coupling areas in which each of them iselectrically connected to one or more subsets of the conductive regions,respectively, via conductive paths. By this, the user can choose one ormore coupling areas. If, for instance, the user places his/her finger(s)on one of the coupling areas, only a certain subset of the regions willhave the same electric potential as the user's finger(s). If thedetection device is sufficiently sensitive, only this subset can bedetected. Thus, the user can activate the detection of certain subsetsand deactivate the detection of the remaining subsets. This can, forinstance, be used to enable the user to make a yes/no decision.

In the generally two-dimensional shape of the information carrier, itmay be preferred to place the coupling area(s) on the same side as thepattern with conductive materials. This allows a simple productionprocess. Another option is to place the coupling area(s) on the sideopposite to the conductive regions. This may be advantageous since theside with conductive regions is generally not easily accessible (sincegenerally in contact with the touch screen) by the user when interactionwith the touch screen is performed. In particular, it may be preferableto have the whole side opposite to the pattern as a coupling area. Inthis case, the user would not have to touch a designated area of thisside, but simply any point on this side. This could allow an easier andmore user-friendly operation. Yet another preferred option is to placethe coupling area in such a way that it can be accessed from both sides.Furthermore, any combination of these options, for example, having oneor more coupling areas on the same side as the conductive regions andone or more coupling areas on the opposite side is also envisaged.

The present disclosure furthermore relates to a kit or system comprisinga product and an information carrier, the information carrier beingreleasably connected or permanently fixed to the product or part of theproduct itself, e.g. by using the material of the product as a substratefor the information carrier. Releasable connections may include, but arenot limited to, magnetic connection, hook-and-loop fasteners, techniquesmaking use of vacuum, non-permanent adhesives, form-locked fixing,material-locked fixing and the like. Permanent fixation may include, butis not limited to, the two objects being glued to each other (withpermanent glue), the information carrier being printed onto the product.The product mentioned above may be any object which one desires toconnect to the information carrier. Examples for this include, but arenot limited to, packages, dishes, printed products, clothes, furniture,documents, toys, consumer goods, food, semi-finished products, (partsof) machine(s), building materials, electrical goods and/or reusablematerials (e.g. bottles).

The method further comprises a detection device, that has a touch screenand wherein is adapted to decode information upon interaction with aninformation carrier comprising a dielectric and/or conductive patternwhich encodes the information, wherein the interaction is based on adifference in the dielectric coefficient and/or the conductivity of thepattern, and wherein the interaction is induced by relative motionbetween the information carrier and the touch screen. It is preferredthat the touch screen is adapted to detect the dielectric/conductivepattern. It is also preferred that the detection device is adapted todetect whether the information carrier interacts with the detectiondevice. Further, it is preferred that decoding of information is atleast partially performed by a computer program.

This is particularly advantageous over prior art technologies since theread out is performed by a touch screen. In contrast to the specializeddetection devices, a touch screen is a detection device which is commonin numerous electronic devices. This makes this technology more economicand versatile than the formerly known solutions.

In the context of the present invention, a dielectric pattern is apattern defining areas or regions having different dielectricproperties, in particular different dielectric coefficients. In thecontext of the present invention, a conductive pattern is a patterndefining areas or regions having different conductive properties, inparticular different conductivities. The dielectric coefficient and/orconductivity may vary continuously over the pattern or in discretesteps. The pattern may comprise two distinct coefficients or a pluralityof predefined dielectric coefficients/conductivities. That is, an objectwith a dielectric or conductive pattern is an object where the specificdielectric coefficient or conductivity depends from the position on theobject. This may be achieved, for example, by providing an objectcomprising materials with different dielectric coefficients and/orconductivities. It may also be achieved by providing an object with aposition dependent density.

Preferably, the information carrier comprises a substrate comprising afirst material with a first dielectric coefficient ε1, wherein thepattern is formed by said substrate and one or more regions of a secondmaterial with a second dielectric coefficient ε2, the second coefficientε2 being different from the first coefficient ε1. Other termini for thedielectric coefficient may include capacitivity, dielectric constant,dielectric permittivity, inductive capacity, permittivity and/orrelative permittivity.

It is preferred to provide the information carrier in such a way thatthe first material, i.e. the material of the substrate, isnon-conductive and the second material is conductive. This may also beinverted. Thus, the dielectric/conductive contrast is enhanced. Exampleelectrically conductive materials include, without being limited to,metals, metal particles, materials comprising conductive particles,conductive polymers or any combination of the mentioned materials. It ispreferred that the conductive particles comprise carbon black and/orgraphite particles. Beyond these materials salts and electrolytes arealso possible, as well as liquids, inks and fluids and/or combination ofthe mentioned materials. It is preferred that liquids, fluids and thelike materials get gelled and/or cured, tempered or in any other waystabilized for further processing and/or handling. Stabilizing can alsobe reached by penetration of the fluids into a soaking surface.

In case the first and second materials are non-conductive andconductive, respectively, the information carrier may comprise any ofthe features discussed above with respect to the inventive informationcarrier, alone or in combination.

In the context of the present invention, a touch screen is an electronicvisual display that can detect the presence and/or location of a touchby a human finger and/or a stylus. A touch screen is a generallytwo-dimensional sensing structure which can detect where it is touched.

These touch screens are common in (but not limited to) smart phones,mobile phones, displays, tablet-PCs, tablet notebooks, graphic tablets,television devices, trackpads, touchpads, input devices, PDAs, and/orMP3 devices. Technologies to perform this detection include resistive,capacitive, acoustic and optical technologies.

According to the invention, the interaction between the informationcarrier and the touch screen can be one of the above-mentionedinteractions. A capacitive interaction between the information carrierand the detection device is generally preferred. Preferably, the touchscreen is adapted to detect the dielectric/conductive pattern (of theinformation carrier), i.e. it has a sensitivity which is sufficient todetect the difference in the dielectric coefficient/conductivity of thepattern. For this purpose, the pattern could be designed such as toallow its detection by the detection device. Vice versa the spatialresolution of the detection device and its resolution in term ofmeasuring a change in capacity could be adapted to the type of thepattern.

It is preferred that the detection device is adapted to detect whetherthe information carrier interacts with the detection device or wherein aproximity between the information carrier and the touch screen isdetected by the detection device. This may be achieved by including acertain threshold signal strength, in particular a threshold for thecontrast in the received signal, beyond which actions are performed. Itis preferred that the detection device can also operate when there is aninteraction between the detection device and two or more informationcarriers. This may allow the system to perform more complex operations.One example how this can be used is by accessing a restricted area onlywhen two information carriers are presented to the system at the sametime (e.g. a laboratory which may not be entered by a single person forsecurity reasons).

It is preferred, that the interaction between information carrier andtouch screen generates a touch signal. A touch signal in the context ofthis patent is a signal in a detection device with a touch screen thatis analogous or at least similar to a signal generated when the touchscreen is touched by one or more fingers of a user. In other words, thepattern of the information carrier is designed to generate a signal on atouch screen which imitates a “typical” finger touch. Accordingly, sizeand shape of the structures forming the pattern may be chosenaccordingly as well as their arrangement. Furthermore, the materialsused by the pattern may be chosen accordingly.

Alternatively, the touch screen may be adapted by appropriate softwareand/or hardware changes that it recognized the pattern of theinformation carrier even though the pattern does not simulate a“typical” finger touch. Rather, the touch screen recognized a minimumdifference in capacity and/or dielectric coefficient in between thefirst and second materials so as to be able to decode the encodedinformation.

Preferably, this touch signal is a capacitive one. This may correspondto a capacitive interaction between the information carrier and thetouch screen. It may also be preferred that this procedure (or method)comprises a further step of decoding information encoded by thedielectric and/or conductive pattern by means of the detection device.This would then allow this method to read out information formerly notknown by the detection device. The method may also comprise a furtherstep of inducing events in the system. Examples include, but are notlimited to, logging onto the system, getting access to certain(restricted) areas (of the system and/or to the internet), starting aprogram, doing a payment and/or verification, upload and/or downloadcontent, play a game, control and/or manipulate programs, alteration ofnumerical values and/or part(s) of text, manipulation of graphics,alteration of data and the like.

Inducing the interaction between the information carrier and the touchscreen may be achieved in different ways. One preferred way to achievethis is to bring the information carrier and the touch screen into atleast partial direct contact. In the context of the present invention,this means that the touch screen and the information carrier touch eachother (at least partially). One preferred way to do this is by placingat least a part of the information carrier on at least part of the touchscreen. This may for example be done by holding the information carrieronto the touch screen or by laying the information carrier on top of thetouch screen, or vice versa. Holding can either be performed manually bythe user or by a mean adapted to hold the information carrier inposition. However, the partial contact is not limited to a static one.

It is preferred that the interaction between the information carrier andthe touch screen is induced by relative motion. The relative motionincludes especially manipulating gestures, deictic gestures, symbolicgestures, emulating gestures and/or imitating gestures or aslide-through-gesture, a slide-in-gesture, a turnkey-gesture, putting,slapping, crumpling, rubbing and/or a combination of these. Furthermore,multi-touch are also preferred, comprising taps, double taps, scroll,pan or flick. A person skilled in the arts knows that gestures representa non-verbal way of communication. In respect to the present invention,it is a communication between an information carrier and a touch screen.The information carrier can interact in various ways with the touchscreen and it was very surprising, that the interaction can occur inform of a relative motion.

For example it is possible to swipe at least a part of the informationcarrier across at least a part of the touch screen. Using relativemotions or especially gestures is preferred when the information carrieris stationary and the touch screen is moving, the touch screen isstationary and the information carrier is moving or the touch screen andthe information carrier are moving. This may be advantageous if thetouch screen is part of a relatively large device which cannot be movedeasily (e.g. the display of an ATM machine) and/or the informationcarrier is small and can therefore be easily handled. Anotherpossibility is to move, for example to swipe at least part of the touchscreen across at least part of the information carrier. This may bepreferred in case the touch screen is part of a small device (e.g. asmart phone) that can easily be handled and/or the information carrieris either large in itself or connected in such a way that it cannot behandled easily (e.g. fixed to a heavy item). It is also preferred thatthe detection device and/or the information carrier is moved. It may beadvantageous, if the information carrier is moved relative to thedetection device or if the detection device is moved relative to theinformation carrier. Furthermore, moving the detection device comprisingthe touch screen across the information carrier may be advantageous (infact, sometimes even necessary) if the (generally two-dimensional) sizeof the information carrier is larger than the area of the touch screen.It is also preferred that the detection device and/or the informationcarrier is aligned in a vertical or horizontal orientation. Thedetection device and/or the information carrier can be for exampleattached to a vertical wall or arranged on a table (or as a table). Theperson skilled in the art is familiar with various methods or techniquesof attaching a device or in general an object to another static ormoving object.

In the context of relative motion between the information carrier andthe touch screen, it is also preferred that the properties of the motionencode information which may lead to events, optionally differentevents. The properties of the motion include, but are not limited to,direction of the motion, speed of the motion and the like. An examplemay be that a user can log onto a computer system (or start a program)by moving the information carrier into one direction. Moving theinformation carrier into the other direction may lead to log out (or theprogram being terminated). However, for the interaction to besufficiently strong, it may not even be necessary to bring theinformation carrier and the touch screen into direct contact, i.e. tomake these two devices touch each other. It was very surprising thateven the contact time or each single time of interaction or especiallythe time of the relative motion occurs for less than 1 minute, preferredfor less than 30 seconds and especially preferred for less than 15seconds. Inducing an interaction may also be achieved by bringing theinformation carrier into proximity of the touch screen, preferablywithin 2 cm of the touch screen. A rather small range of interaction isadvantageous in terms of security over, e.g., RFID technology, sincesensitive information cannot be read out over large distances.

Again, it is preferred that the preferred method can be applied to bothusing a single information carrier and using two or more informationcarriers at the same time. It may also be preferred that the two or moreinformation carriers are not presented to the detection device at thesame time, but at least partially shifted in time. This may beadvantageous as it allows more complex operations or as a feature withinthe concrete application of the information carrier.

It is also preferred that the interaction between a user of thedetection device, the touch screen and/or the information carriercomprises the following interactions:

-   -   a. the user is interacting with the information carrier,    -   b. the information carrier is interacting with the touch screen,    -   c. the user is interacting with the information carrier and the        touch screen,    -   d. the information carrier is interacting with the user and the        touch screen and/or    -   e. the touch screen is interacting with the user and the        information carrier.

The user can have two or more connections with the information carrier.It was previously described that the information carrier can comprisecoupling areas. The user can touch or interact with for example thecoupling area and another conductive area on the information carrier.This allows to generate complex interactions between the informationcarrier and the touch screen. In the sense of the invention, the term“connections” describes an interaction between the user and theinformation carrier and comprises preferably that the user touches theinformation carrier. However, it is also preferred, that at least twousers are connected to the information carrier and/or are interactingwith the touch screen.

In a preferred method, a feedback is returned from the detection deviceand/or a device connected to the detection device by haptic perception,tactile perception, auditory perception and/or visual perception. It maybe advantageous, when the detection device indicates whether aninteraction with the information carrier was successfully established ornot. Therefore, the detection device comprises means that allow forpositive or negative feedback in form of haptic, tactile, auditoryand/or visual feedback. It is also preferred that the feedback isreturned by means that are connected to the detection device rather thanpart of it. For example, speakers, displays, microphones or otherdevices for transmitting and reproducing sound and/or images can beconnected to the detection device by cable or wireless (e. g. Bluetooth,optical transmission, acoustic transmission). However, the feedback canalso returned by means that are part of the detection device in additionor instead to the means that are connected to the detection device.

Furthermore, it was very surprising that the interaction between theinformation carrier and the detection device can be improved by thedevice vibrating during the interaction. However, it is also preferredthat the device is vibrating after the interaction to indicate asuccessful or unsuccessful interaction. In this context, it may bepreferred, that the device gives a tactile, acoustic and/or visualsignal before, during and/or after the interaction. The signal may alsoindicate a successful or unsuccessful interaction. In a preferredembodiment, the signal can be used as a guiding system for the user tooptimize or improve the interaction between the information carrier andthe detection device, especially the touch screen. Furthermore, it ispreferred, that the information carrier has supporting features. Thesesupporting features allow to align the information carrier in an optimalway with the detection device, especially the touch screen. The featurescomprise mechanical, tactile, haptic or other means for improving thepositioning of the information carrier. It is further preferred that thedetection device and/or the touch screen comprises magnetic, mechanical,acoustic, tactile and/or visual positioning means, helping to improvethe positioning of the information carrier on the touch screen of thedetection device.

In a preferred method, the detection device is detecting whether theinformation carrier interacts with the touch screen. It was verysurprising to adapt the detection device in a way, that it easilydetects the proximity of the information carrier. Preferred detectiondevices contain a photosensor, measuring the light intensity. The sensorcan be modified to detect the information carrier, as moving theinformation towards the touch screen shades the screen from light, whichcan be detected by the detection device. The shaded area on the touchscreen can also be used to differentiate between an information carrierand a finger, triggering different events or actions.

It may also be preferred that the information carrier corresponds to astored data set in a data processing system. This data set may be eitherstatic or dynamic.

It may also be preferred that the information carrier corresponds to acertain event in the data processing system. This means that theinformation carrier could be used to induce this event.

The invention also relates to a system performing the preferred methodcomprising:

-   -   a. an information carrier comprising a dielectric and/or        conductive pattern which encodes information and    -   b. a detection device having a touch screen; the detection        device is able to decode the information upon interaction        between the information carrier and the touch screen, wherein        the interaction is caused by a difference in the dielectric        coefficient and/or the conductivity of the pattern.

The features concerning the preferred method also apply to the preferredsystem and vice versa.

It is preferred that the system comprises an information carriercomprising a dielectric and/or conductive pattern which encodesinformation and a detection device having a touch screen, wherein thedetection device is adapted to decode the information upon interactionbetween the information carrier and the touch screen, wherein theinteraction is based on a difference in the dielectric coefficientand/or conductivity of the pattern. The information carrier may have anyof the features discussed above with respect to the method.

It is preferred, that the size of the information carrier is smallerthan the size of the touch screen or the size of the information carrieris equal to the size of the touch screen or the size of the informationcarrier is bigger than the size of the touch screen. The interactionbetween the information carrier and the touch screen can be improved byvarious supporting features, that can be on the information carrier, oron the touch screen and/or in the depiction on the touch screen,comprising tactile, haptic, optical, acoustical, mechanical and/ormagnetic features. Therefore, it may be advantageous when the systemcomprises at least one mean for the determination of pressure, force,visual information, acoustic information, proximity, movement, tiltand/or orientation. This mean might be a sensor or another device formeasuring these physical features. In addition to the supportingfeatures, which improve the interaction between the information carrierand the touch screen, the detection, the touch screen and/or theinformation carrier comprises at least one magnetic, mechanical,acoustic, tactile and/or visual positioning mean. The supporting meangives for example a feedback of a successful interaction, whereas thepositioning mean is for aligning or positioning the information carrieron the touch screen in an optimal way.

Furthermore, it is preferred that the system provides information aboutthe states and/or actions comprising:

-   -   the user needs assistance,    -   the user has a connection to the touch screen,    -   the user has no connection to the touch screen,    -   the user has a connection to the information carrier,    -   the user has no connection to the information carrier,    -   the position of the information carrier was determined,    -   the orientation of the information carrier was determined,    -   the distance between the information and the touch screen was        determined,    -   the touch screen has moved,    -   the touch screen has not moved,    -   the touch screen is moving,    -   the information carrier has moved,    -   the information carrier has not moved,    -   the information carrier is moving,    -   the user has moved,    -   the user has not moved,    -   the user is moving.

According to the present invention, one can use any suitable patterndetectable by a touch screen to encode information on an informationcarrier. That is, one is not limited to make use of the dielectricand/or conductive pattern (though this one has certain advantages asdescribed above). Generally, any method with the following steps issuitable to read out information readable by a touch screen: providingan information carrier with a pattern that encodes information and adetection device having a touch screen; inducing an interaction betweenthe information carrier and the touch screen; detecting a signalcorresponding to the pattern with the detection device and decoding thesignal to retrieve the encoded information, wherein the interaction isinduced by relative motion between the information carrier and the touchscreen. One preferred option is that the signal decoding is performed bythe detection device. Any pattern detectable by the detection devicehaving a touch screen can be used.

Examples include, but are not limited to, the dielectric and/orconductive pattern as described and a pattern formed by spatialdeviations of an information carrier.

It is also preferred to have a detection device having a touch screen,wherein the detection device is adapted to decode information encodedwithin a pattern of an information carrier upon interaction of saidinformation carrier with the touch screen by means of a decodingalgorithm. In particular, it is preferred to use a computer program forthis task.

Again, the inventive method is not limited to the use of only oneinformation carrier. One may use one or more information carriers. Thiscould, for example, allow for more complex operations.

The basic idea of the present invention is not limited to touch screens.Other capacitive devices whose mode of detection is based on capacitiveinteraction may be utilized as well. In particular, other touch devicessuch as touch pads or track pads may be used for the present invention.For example, information encoded on an information carrier may betransferred to a laptop by placing the information carrier on the touchpad or track pad of the laptop, which identifies the pattern viacapacitive interaction. Accordingly, the detection device may compriseanother touch device rather than a touch screen and the method mayutilize another touch device rather than a touch screen, preferably atouch pad or track pad.

The present invention is further directed to a computer programcomprising program code means for performing the following steps whensaid program is run on a detection device having touch screen: decodinga signal detected by the touch device/touch screen of the detectiondevice to retrieve data representing information encoded in the signal;and inducing an event in the detection device based on the retrieveddata.

Although the invention has been described with respect to specificembodiments and examples, it should be appreciated that otherembodiments utilizing the concept of the present invention are possiblewithout departing from the scope of the invention. The present inventionis defined by the claimed elements, and any and all modifications,variations, or equivalents that fall within the true spirit and scope ofthe underlying principles.

The present invention is described by way of examples in more detailbelow referring to the following Figures:

FIGS. 1 to 5 Preferred embodiments of a information carrier

FIGS. 6 to 25 Examples of interactions between an information carrierand a detection device with a touch screen

FIGS. 1 to 5 show preferred embodiments of a information carrier. FIG. 1is a top view of an information carrier 1 comprising a substrate 2 of afirst material with the dielectric coefficient ε1 and a dielectricpattern formed by regions 3 of a second material with the dielectriccoefficient ε2 and the substrate 2. In other words, the dielectricpattern comprises most of the surface of the substrate 2, on the onehand, and the regions 3, on the other hand. The substrate 2 preferablycomprises a non-conducting material such as plastics, syntheticmaterials, paper, carton, (derived) timber products, compositematerials, ceramics, glass, cloths, textiles, leather or any combinationof the mentioned materials. The regions 3 preferably comprise aconducting material such as metals, metal particles, materialscomprising conductive particles, conductive polymers, carbon blackand/or graphite, salts, electrolytes or any combination of the mentionedmaterials.

The regions 3 forming the pattern together with the substrate 2 may beof different shapes and/or sizes, possible shapes including (but notlimited to) circles or squares. Yet, any other shape not representedwithin the Figures may be used. A single information carrier maycomprise a pattern with regions 3 of different shapes and/or sizes, theshapes including circles, rectangles, squares, triangles and/or othershapes. It is preferred that the regions 3 are separated by apredetermined distance, at least 20 μm, preferably at least 1 mm. Thus,the different regions 3 may me distinguished by a touch screen asseparate regions.

Preferably, the regions 3 forming the pattern are arranged or applied ontop of the substrate 2. Yet, the pattern may also be applied to thebottom of the substrate 2. The substrate 2 may also be provided with apattern of recesses, the recesses being filled with the second material.Thus, a completely flat surface of the pattern may be achieved even incase of the regions having a thickness disturbing the impression of asmooth surface. It is generally preferred that the pattern formed by thesubstrate 2 and the regions 3 is substantially flat.

A substantially flat surface may be achieved by printing or laminatingthe regions 3 onto the substrate 2. Even though the printed or laminatedregions 3 will have a certain thickness, the surface will neverthelessbe considered as substantially flat by a user due to the impression of asmooth surface. In order to achieve a substantially flat surface theregions 3 may also be embedded within the substrate 2 and/or the top ofthe information carrier 1 may be covered or coated at least partiallywith a layer of additional material.

It is also preferred to provide a grid of conducting lines covering apart or all of one, both or all surfaces of the substrate. Examples ofsuch grids are shown in FIG. 3 and FIG. 4. The grid may consist of aregular pattern of electrically conducting lines or of an irregulararrangement of electrically conducting lines. Other grids or linepatterns as the ones shown may be utilized as well. The grid does notnecessarily have to cover the entire surface of the information carrierbut may also be provided in one or more regions, only. The grid acts asthe coupling area since a user may touch the surface of the carrier atany portion which does comprise the grid. It is in particular preferredto substantially extend the grid to the outer perimeter of the substrate2, e.g. by a surrounding conductive line. This will ensure the couplingeffect at any stage of usage of the information carrier. The conductiveregions 3 may be directly connected to all conductive lines of the gridwhich cross or traverse the regions 3. However, this sometimes causesperturbations to the signals being detected and/or leads to noise in thesignal. It is thus preferred that the conductive regions 3 areelectrically connected to the grid only via some or even only one of theconducting lines crossing or traversing the regions. For example, eachconductive region 3 can be directly connected to two conductive lineswhich cross the regions only, whereas the remaining lines areinterrupted proximate the conductive regions 3. This embodiment issurprisingly less susceptible to faults.

The substrate 3 of the information carrier 1 can be is formed by anon-conducting material and the regions 3 are of conductive material, itis preferred to connect (at least) some of the regions 3 via conductivepaths 4. Their cross section (parallel to the surface of the informationcarrier 1) of these paths 4 may be smaller than the diameter of theregions 3. However, their cross section may also be of an equal or evenlarger size than the diameter of the regions 3. Due to the conductivepaths 4 the regions 3 are on the same electric potential, which may beadvantageous to provide a constant well-defined signal by each region 3.It is preferred to connect at least one of the regions 3 to a couplingarea 5 via conductive paths 4 (see e. g. FIG. 5). Touching the couplingarea 5 with a finger will set the regions 3 electrically connected tothe coupling area 5 on the same electric potential as the user.Furthermore, the capacity measured by the touch screen will more closelyresemble the typical capacitive change induced by a finger touching thetouch screen. When viewed from the top, the position of this couplingarea may include to be located remote from the edges of the substrate 2,as well as on one side edge of the of the information carrier 1.However, other positions (e.g. in one corner) are also possible. It isin particular preferred to provide a coupling area 5 surroundingsubstantially the entire carrier 1 to provide possible touch locationsto a user around the entire edge of the carrier. The coupling area 5 maybe provided on the same side of the carrier as the regions 3.Alternatively, it may be provided on the opposite side (not shown).Thus, a user may touch the coupling area on the back side even if thefront side completely contacts the touch screen. Furthermore, it ispossible that the coupling area 5 coincidences with one or more of theregions 3 of conductive material and/or with one or more of theconductive paths 4. For example the coupling area 5 may coincidence infact with all regions 3 of conductive material. Alternatively, thecoupling area 5 may coincidence with all conductive paths 4. Thecoupling area 5 may be electrically connected to all regions 3.Alternatively, only one or more of the regions 3 are electricallyconnected to the coupling area 5, while one or more of the regions 3 areelectrically insulated from the coupling area 5. In certain embodiments,two or more coupling areas 5 are provided which are connected viaelectric paths 4 to two or more subsets of regions 3 of conductivematerial, as is shown in the embodiment of FIG. 5, in which a firstsubset comprises three regions 3 and a second subset comprises 2 regions3 electrically connected to one coupling area 5, respectively. Thus, theuser may decide which subset of regions 3 is to be set on the user'spotential by touching one of the two coupling areas 5 only. If the touchscreen is sensitive to regions 3 only, which are electrically connectedvia a coupling area to a user, the touch screen will detect the threeregions 3 of the first subset or the two regions 3 of the second subsetdepending on the user's touch location. Accordingly, the type ofdetectable information encoded on the information carrier may beinfluenced by the user choosing a coupling area 5.

The information carrier may also comprise more than two coupling areaswith corresponding subsets of regions 3. For example, a coupling area 5may be provided at each corner and/or each edge and/or each side of theinformation carrier. The different coupling areas may be color coded orotherwise identified to the user as generating a particular signal(corresponding to the particular subset of the pattern).

According to an embodiment of the invention, the embedded regions 3 arecombined with regions 3 on top of the substrate. In other words, thepattern formed by the regions and the substrate don't need to bearranged within one two-dimensional area but may also have a componentin the third dimension. Preferably, the touch screen is adapted todistinguish between embedded regions and regions applied on top due totheir different signal strength.

FIG. 6-11 show interactions between two information carriers 1 and adetection device 8 comprising a touch screen 9. One preferred method toperform this interaction is to place at least part of the informationcarrier 1 on at least part of the touch screen 9. It may be necessary toplace essentially the complete information carrier onto the touch screen9 to generate the appropriate signal. Yet, it is preferred that itsuffices to place only part of the information carrier onto the touchscreen. Thus, a portion of the information carrier remains free whichallows a user to, e.g., easily touch one or more coupling areas. Thesignal generated in the touch screen may depend on the orientation ofthe carrier with respect to the touch screen. Yet, it is preferred thatthe signal does not depend on the orientation. For this purpose, thepattern may comprise a predetermined sub-pattern which is used toidentify the orientation of the carrier with respect to the touchscreen.

One can also (at least partially) place two or more information carriers1 onto different parts of the touch screen 9 of the detection device 8.This allows for more complex operations such as generating signalsdefined by a specific combination of carriers. Preferably, the portionof the information carrier to be put into contact with the touch screenis marked on the carrier to ease its use. Preferably, the one or morecoupling areas are provided in portions which are not to be put intocontact.

It is also preferred that the interaction between the touch screen 9 ofthe detection device 8 and one or more information carrier(s) 1 may beinduced a dynamic interaction rather than a static one. For example,inducing the interaction may comprise moving the information carrierwith respect to the touch screen or vice versa. For example, swiping thedetection device 8 across the information carrier 1 may induce aninteraction. The block array indicates the direction of the movement ofthe detection device 8. On the right side in FIG. 11a , a section acrossthe top view is also included. The direction of movement may be markedon the information carrier for the user's convenience. Movement indifferent directions may also cause different signals to be detected bythe touch screen. Movement includes also rotation or up and downmotions.

FIG. 12 shows the interaction of the information carrier with thedetection device, especially the touch screen of the detection device. Auser 10 can place the information carrier 1 comprising a region 3, togenerate a touch event on the touch screen 9 of a detection device 8 andholding the information carrier 1 simultaneously. However, it may alsopreferred, that the information carrier 1 is placed on the touch screen9 without being hold by the user 10. The information carrier 1 can havevarious sizes in relation to the touch screen 9 (see FIG. 13A-C). It 1can be smaller than, equal to or bigger than the touch screen 9. Thesize does not matter for an interaction to occur. It may only render theway of the interaction. If the information carrier 1 is bigger than thetouch screen 9, it may be advantageous to move the detection device 8over the information carrier 1. However, it is also possible to move theinformation carrier 1 relative to the detection device 8. In thiscontext, it may be advantageous if the information carrier 1 or thedetection device 8 is stationary, whereas the other is mobile (see e.g.FIG. 14A-C). The static one can be aligned in a vertical or horizontalorientation, allowing the user to use either the information carrier 1or the detection device 8 while standing or sitting (see e. g. FIG.15A-C). It is preferred that the information carrier 1 is printed on anobject or that the object is the substrate for the information carrier 1(see FIG. 16A-C). The object carrying the information carrier 1 can bemoved over a detection device 8, that can be oriented in a horizontal orvertical way. The information carrier 1 can also be scant by a detectiondevice 8, wherein the detection device 8 is moved over the informationcarrier 1 (see FIG. 16A-F), when the information carrier is positionedon or at a surface 12. The surface 12 can be part of a bigger object aswell.

The interaction between the information carrier and the touch screen canbe induced in various ways (FIG. 17A-D). The detection device 8 can beapplied to the information carrier 1 to scan it, without the need to betouched by a user 10. However, it can be preferred that a user 10 isapplying the detection device 8 to the information carrier 1 by onlytouching the detection device 8 and/or also the information carrier 1.The information carrier 1 and/or the detection device 8 can also betouched by more than one user 10. It is also possible that two userstouch the information carrier 1 and bring it in contact with a touchscreen 9 of a detection device 8 (see FIG. 18A-B). Furthermore, morethan one information carriers 1 can be brought in contact with the touchscreen 9. This can be done by only one user or more than one user. It isalso possible that the information carrier is touched by two user.

The interaction between the information carrier 1 and the touch screen 9is preferably induced by relative motion between both of them (FIG.19A-C). Gestures can be used to apply the information carrier 1 to thetouch screen 9 (e. g. slide-through, slide in or turn-key gestures)Arrows indicate the direction of movement.

To optimize the interaction between the information carrier 1 and thedetection device 8, especially the touch screen 9, it is preferred thatthe detection device 8 and/or the information carrier 1 return afeedback upon successful or unsuccessful interaction (FIG. 20A-C). Thefeedback may comprise haptic, tactile, acoustic or visual feedback orcombination of these. The information carrier 1 e. g. can compriserecesses and the detection device 8 can return tactile (FIG. 20A),acoustic (FIG. 20B) and/or visual (FIG. 20C) feedback. Furthermore, itis preferred that the information carrier 1 and/or the detection device8 and/or the touch screen 9 contain means for positioning theinformation carrier 1 on the touch screen 9 (FIG. 21). The meanscomprise for example mechanical means such as an edge (FIG. 21), thatallow the orientation of the information carrier 1 on the touch screen 9in only one specific way. It is also possible to use the user (e. g. thehand of the user 10) as a limitation of movement in order to positioningthe information carrier 1 in the correct way (FIG. 22). Using thesepositioning means, it is also possible to enhance the interaction or atleast increase the possibility of interaction.

Specific visual effects of the touch screen 9 of the detection device 8can interact with the information carrier 1 and generate new information(FIG. 23). This can be realized by recesses 11 on the informationcarrier 1 or by translucent material of the information carrier 1.

It is preferred that the detection device 8 differentiates between atouch signal generated by a finger of an user 10 or by an informationcarrier 1 (FIG. 24). This differentiation reduces mistakes in usage orinteraction. The different touch signals can be displayed by the touchscreen 9 in different colours or forms.

It is advantageous that the information carrier 1 with a region 3 can bepartially applied to the touch screen 9, without failing to generate afeedback (FIG. 25). The feedback or guiding system or support system isfor example to invite the user to place the information carrier 1differently or fully on the touch screen 9.

1. A method with the following steps: a. providing one or moreinformation carrier(s) with a dielectric and/or conductive pattern and adetection device having a capacitive touch screen and b. inducing aninteraction between the information carrier and the touch screen,wherein the interaction is based on a difference in the dielectriccoefficient and/or the conductivity of the pattern and generates a touchsignal and c. wherein the interaction is inducted by relative motionbetween the information carrier and the touch screen.
 2. A methodaccording to claim 1, wherein the relative motion includes manipulatinggestures, deictic gestures, and/or symbolic gestures, emulating gesturesand/or imitating gestures.
 3. A method according to claim 1, wherein therelative motion includes a slide-through-gesture, a slide-in-gesture, aturnkey-gesture, putting, slapping, crumpling, rubbing and/or acombination of these.
 4. A method according to claim 1, wherein afeedback is returned from the detection device and/or a device connectedto the detection device by haptic perception, tactile perception,auditory perception and/or visual perception.
 5. A method according toclaim 1, wherein inducing the interaction is achieved by bringing theinformation carrier and the touch screen into at least partial directcontact.
 6. A method according to claim 1, wherein the interaction isinduced by placing at least a part of the information carrier on atleast a part of and the touch screen.
 7. A method according to claim 1,wherein the detection device and/or information carrier is moved.
 8. Amethod according to claim 1, wherein the device is vibrating duringand/or after the interaction.
 9. A method according to claim 1, whereinthe device gives a tactile, acoustic and/or visual signal before, duringand/or after the interaction.
 10. A method according to claim 1, whereinthe information carrier has supporting features.
 11. A method accordingto claim 1, wherein the detection device comprises magnetic, mechanical,acoustic, tactile and/or visual positioning means.
 12. A methodaccording to claim 1, wherein a proximity between the informationcarrier and the touch screen is detected by the detection device.
 13. Amethod according to claim 1, wherein each single interaction occurs forless than 1 minute, preferred for less than 30 seconds and especiallypreferred for less than 15 seconds.
 14. A method according to claim 1,wherein the interaction between a user of the detection device, thetouch screen and/or the information carrier comprises the followinginteractions: the user is interacting with the information carrier, theinformation carrier is interacting with the touch screen, the user isinteracting with the information carrier and the touch screen, theinformation carrier is interacting with the user and the touch screenand/or the touch screen is interacting with the user and the informationcarrier.
 15. A method according to claim 1, wherein the informationcarrier is stationary and the touch screen is moving, the touch screenis stationary and the information carrier is moving or the touch screenand the information carrier are moving.
 16. A method according to claim1, wherein the user has two or more connections to the informationcarrier.
 17. A method according to claim 1, wherein at least two usersare connected to the information carrier and/or are interacting with thetouch screen.
 18. A method according to claim 1, wherein the detectiondevice and/or information carrier is aligned in a vertical or horizontalorientation.
 19. A method according to claim 1, wherein the detectiondevice is detecting whether the information carrier interacts with thetouch screen.
 20. A system performing the method according claim 1comprising: a. an information carrier comprising a dielectric and/orconductive pattern which encodes information and b. a detection devicehaving a touch screen; the detection device is able to decode theinformation upon interaction between the information carrier and thetouch screen, wherein the interaction is caused by a difference in thedielectric coefficient and/or the conductivity of the pattern. 21-27.(canceled)